Video files have become ubiquitous. One popular type of file format used for video files is Flash Video (FLV). FLV is a proprietary file format used to deliver video over the Internet. Flash Video is viewable on most operating systems, via the widely available Adobe Flash Player™ and web browser plugin, or one of several third-party programs. The Adobe Flash Player is a multimedia and application player developed and distributed by Adobe Systems, Incorporated of San Jose, Calif. Because the Flash Player runs as a browser plug-in, it is possible to embed Flash Video in web pages and view the video within a web browser. Audio in Flash Video files is usually encoded as Moving Picture Experts Group audio layer 3 (MP3). FLV files also support uncompressed audio or Adaptive Differential Pulse Code Modulation (ADPCM) format audio.
Compared to other plug-ins such as Java, Acrobat Reader, QuickTime or Windows Media Player, the Flash Player has a small install size, quick download time, and fast initialization time.
Since its introduction, Flash technology has become a popular method for adding animation and interactivity to web pages; several software products, systems, and devices are able to create or display Flash. Flash is commonly used to create animation, advertisements, various web-page components, to integrate video into web pages, and more recently, to develop rich Internet applications.
Many websites rely on Flash being available by default on a user's web browser and will not check to see if it is available. If Flash is not installed, users may be unable to access some Flash-dependent websites or site features. These sites sometimes depend on a fast Internet connection, especially a highly complex website or one with music. While it is not impossible to see Flash-based sites with a slower form of Internet, such as dial-up, or a slow form of Digital subscriber Loop (DSL), it may be frustrating for the user. Blocking tools generally do alert the end user to the fact that Flash content is present on the site, allowing the user to view it if they wish.
Flash is increasingly used as a way to display video clips on web pages. The Adobe Flash Player is a dedicated browser plugin (also available as standalone player) and offers very good platform compatibility compared to other browser plugins. It is available for many popular platforms, including Windows, Mac OSX and—to some extent—Linux. Flash is used as the basis for many popular video sites, including YouTube and Google Video
Flash as a format has become very widespread on the desktop market. Flash players exist for a wide variety of different systems and devices. Flash content can run consistently on Microsoft Windows, Mac OS, and Linux.
Of late, Flash libraries are being used with the XML capabilities of the browser to render rich content in the browser. Since Flash provides more comprehensive support for vector graphics than the browser and because it provides a scripting language geared towards interactive animations, it is considered a viable addition to the capabilities of a browser.
Many times, Flash authors will decide that while they desire the advantages that Flash affords them in the areas of animation and interactivity, they do not wish to expose their images and/or code to the world. However, once an .swf file is saved locally, it may then quite easily be decompiled into its source code and assets. Some decompilers are capable of nearly full reconstruction of the original source file, down to the actual code that was used during creation.
In opposition to the decompilers, SWF obfuscators have been introduced to provide a modicum of security, some produced by decompiler authors themselves. The higher-quality obfuscators use traps for the decompilers, making some fail, but none have definitively been shown to protect all content.